Alkoxyamines containing unsaturated groups

ABSTRACT

The invention relates to new alkoxyamines suitable for hydrosilylation reactions, to siloxane modified alkoxamines and to siloxane modified polymers as well as to their use. The alkoxamines are compounds of formula (I) or (II) wherein A is a group capable of forming a stable free nitroxyl radical A. which is bound via its oxygen atom to the carbon atom; R.sub.1 and R.sub.2 independently of one another are hydrogen, C.sub.1-C.sub.18-alkyl, C.sub.3-C.sub.8cycloalkyl or phenyl which are unsubstituted or substituted by NO.sub.2, halogen, amino, hydroxy, cyano, carboxy, C.sub.1-C.sub.4alkoxy, C.sub.1-C.sub.4alkylthio, C.sub.1-C.sub.4alkylamino or di(C.sub.1-C.sub.4alkyl)amino; R.sub.3, R.sub.4 and R.sub.5 independently of one another are hydrogen or C.sub.1-C.sub.18alkyl or phenyl; or R.sub.3 and R.sub.5 together with the linking group C.dbd.C form a 5 to 12 membered ring; R.sub.6 is X hydrogen or C.sub.1-C.sub.l8alkyl or phenyl; X is O, NH or NR.sub.7, wherein R.sub.7 is C.sub.1-C.sub.18alkyl, C.sub.3-C.sub.8cycloalkyl or phenyl; Y is a direct bond, C.sub.1-C.sub.30alkylene or C.sub.6-C.sub.12arylene.

This application is a National Stage completion of PCT/EP2006/067410 filed Apr. 23, 2008, which claims priority from European Patent Application EP-05110005.5 filed Oct. 26, 2005.

The invention relates to new alkoxyamines suitable for hydrosilylation reactions, to siloxane modified alkoxamines and to siloxane modified polymers as well as to their use.

The International Publication WO2004/029156 (Ciba) describes a process for the preparation of a triblock-copolymer or graft-copolymer via controlled free radical polymerization using NOR functional polysiloxanes. A polysiloxane is reacted with an ethylenically unsaturated functional alkoxyamine of formula (I)

under hydrosilylation conditions. Polymers containing e.g. poly-styrol-polysiloxane-poly-styrol blocks are obtained.

Chem. Commun., 2004, 174-175 describes radical cyclization reactions using alkoxyamines as starting material. The alkoxamines disclosed therein are disclaimed.

It has been found that using specific alkoxyamines as hydrosilylation agent, siloxane modified alkoxamines having an improved activity in polymerising acrylates can be obtained.

One aspect of the invention is a compound of formula (I) or (II)

wherein

A is a group capable of forming a stable free nitroxyl radical A• which is bound via its oxygen atom to the carbon atom;

R₁ and R₂ independently of one another are hydrogen, C₁-C₁₈-alkyl, C₃-C₈cycloalkyl or phenyl which are unsubstituted or substituted by NO₂, halogen, amino, hydroxy, cyano, carboxy, C₁-C₄alkoxy, C₁-C₄alkylthio, C₁-C₄alkylamino or di(C₁-C₄alkyl)amino;

R₃, R₄ and R₅ independently of one another are hydrogen or C₁-C₁₈alkyl or phenyl; or R₃ and R₅ together with the linking group C═C form a 5 to 12 membered ring;

R₆ is hydrogen or C₁-C₁₈alkyl or phenyl;

X is O, NH or NR₇, wherein R₇ is C₁-C₁₈alkyl, C₃-C₈cycloalkyl or phenyl;

Y is a direct bond, C₁-C₃₀alkylene or C₆-C₁₂arylene,

with the proviso that the compound of formula I is not

Another aspect of the invention is a polysiloxane modified initiator/regulator of the formula

wherein

A, R₁, R₂, R₃, R₄, R₅, R₆, X and Y independently of one another are as defined above under formula (I) or (II) and

a is 1 or 2, or a whole number between 1 and 100,

W is a linear or branched monofunctional, difunctional or multifunctional polysiloxane residue.

Furthermore the invention relates to a siloxane modified polymer or copolymer which is obtained by

-   -   a) reacting a Si—H functionalized polysiloxane in the presence         of a functional alkoxyamine initiator/regulator compound of the         formula (I) or (II) as defined above under hydrosilylation         conditions to obtain alkoxyamine functional polysiloxanes (Ia),         (IIa) or (IIb)     -   b) reacting the resulting alkoxyamine functional polysiloxane         (Ia), (IIa) or (IIb) with at least one vinylic monomer at a         temperature between 60 and 160° C.

Furthermore the invention relates to the use of a siloxane modified polymer or copolymer which is obtained as described above as slip and leveling agent or as dispersant.

Furthermore the invention relates to the use of a siloxane modified polymer or copolymer as slip and leveling agent or as dispersant, whereby the polymer or copolymer is obtained by

-   -   a) reacting a Si—H functionalized polysiloxane in the presence         of a functional alkoxyamine initiator/regulator compound of the         formula (III), (IV), (V) or (VI)

-   -    under hydrosilylation conditions to obtain alkoxyamine         functional polysiloxanes (IIIa), (IVa or IVb), (Va), (VIa or         VIb)

-   -    wherein A, R₁, R₂, R₃, R₄, R₅, R₆, X and Y, W, a are as defined         above under formula (I)     -   c) reacting the resulting alkoxyamine functional polysiloxane         with at least one vinylic monomer at a temperature between 60         and 160° C.         Preferences

Preferred is a compound of the formula I and a siloxane modified initiator of the formula Ia and a siloxane modified polymer or copolymer which is obtained by

-   -   d) reacting a Si—H functionalized polysiloxane in the presence         of a functional alkoxyamine initiator/regulator compound of the         formula (I) under hydrosilylation conditions to obtain         alkoxyamine functional polysiloxanes (Ia),     -   e) reacting the resulting alkoxyamine functional polysiloxane         with at least one vinylic monomer at a temperature between 60         and 160° C.         Vinylic Monomers

The vinylic monomer is selected from the group consisting of acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, acrylic acid (C₁-C₂₂)alkyl esters, acrylic acid (C₁-C₂₂)-hydroxyalkyl esters, methacrylic acid (C₁-C₂₂)alkyl esters, methacrylic acid (C₁-C₂₂)hydroxy-alkyl esters, acrylic acid (C₁-C₂₂)alkyl esters or methacrylic acid (C₁-C₂₂)alkyl esters which are substituted by amino, (C₁-C₂₂)alkylamino, (C₁-C₂₂)dialkylamino, —SO₃H, epoxy, fluoro, perfluoro or siloxane groups, styrene, substituted styrene, acrylamide and methacrylamide, N-mono(C₁-C₂₂)alkyl acrylamide, N,N-di(C₁-C₂₂)alkyl acrylamide; provided that the amount of unsubstituted acrylic acid (C₁-C₂₂)alkyl esters or/and methacrylic acid (C₁-C₂₂)alkyl esters is more than 30% by weight based on the weight of the total monomer mixture.

Preferably the vinylic monomer is styrene, methylacrylate, ethylacrylate, n-butylacrylate, iso-butylacrylate, tert. butylacrylate, hydroxyethylacrylate, hydroxypropylacrylate, dimethyl-aminoethylacrylate, glycidylacrylates, methyl(meth)acrylate, ethyl(meth)acrylate, butyl(meth)-acrylate, hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, dimethylaminoethyl-(meth)acrylate, glycidyl(meth)acrylates, acrylonitrile, acrylamide, methacrylamide or dimethylaminopropyl-methacrylamide or mixtures of them.

In a preferred embodiment the vinylic monomer is an acrylic monomer.

If the siloxane modified polymer is used as slip and leveling agent the especially preferred vinylic monomer is selected from methylacrylate, ethylacrylate, ethylhexylacrylate, propyl-acrylate, cyclohexylacrylate, hydroxyethylacrylate, n-butylacrylate, styrene, vinylpyridine.

If the siloxane modified polymer is used as dispersant the especially preferred vinylic monomer is an acrylic acid (C₁-C₂₂)alkyl esters or methacrylic acid (C₁-C₂₂)alkyl esters which are substituted by amino, (C₁-C₂₂)alkylamino, (C₁-C₂₂)dialkylamino, e.g. dimethylaminoethyl-(meth)acrylate.

In the context of this invention, the term “polymer” refers to a polymer of any type including homopolymers and copolymers. The term “copolymer” is meant to include polymers containing groups or units derived from two or more monomers with random, diblock, and multi-block microstructures. The copolymer can be block(co)polymers, comb(co)polymers, star(co)polymers, dendritic(co)polymers or hyperbranched(co)polymers. Block structures such as diblock, triblock are preferred.

In other words, after completing the polymerization of a first monomer to the extent desired to form a first polymer “block”, a second monomer is introduced into the reaction mass to effect polymerization of the second monomer to form a second polymer “block” that is attached to the end of the first block. Using this sequential addition process, a broad range of diblock, triblock, etc. copolymers can be prepared.

The term “copolymer” also includes gradient copolymers or tapered copolymers which are copolymers composed for example of two monomers or monomer mixtures A and B in whose individual chains there is a gradient in the distribution of the monomer units along the chains. One end of the chain is rich in A units and the other in B units. Such copolymers show a continuous transition of one monomer or monomer mixture A into another monomer of monomer mixture B along the polymer chain.

Polysiloxanes

The Si—H functionalized polysiloxane is linear or branched and is commercially available or can be produced via known methods (Silicone, Chemie und Technologie [Silicones, Chemistry and Technology], Vulkan Publishers, Essen 1989, pp 82-84).

The Si—H functionalized polysiloxanes contains at least one unit corresponding to the general formula H(R₂)₂SiO_(1/2) wherein R is C₁-C₆alkyl or phenyl, preferably methyl. The Si—H unit or Si—H units can be in alpha and/or omega position or can be distributed. Thus, the siloxanes are taken from the group consisting of linear siloxanes, comb-like siloxanes, T-branched siloxanes.

Preferred examples are:

DEFINITIONS

C₁-C₂₈alkyl radicals are linear or branched and are, for example, methyl, ethyl and the various position isomers of propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl or hexadecyl, heptadecyl, octadecyl, nonadecyl or eicosyl.

C₃-C₈cycloalkyl is, for example, cyclopropyl, dimethylcyclopropyl, cyclobutyl, cyclopentyl, methylcyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl.

C₁-C₃₀alkylene bridges are linear or branched and may be interrupted by at least one N or O atom. Preferred are C₁-C₁₂alkylene bridges, more preferably of C₂-C₆alkylene bridges like ethylene, propylene, butylene, pentylene, hexylene.

C₂-C₁₂alkylene bridges interrupted by at least one N or O atom are, for example, —CH₂—O—CH₂—CH₂, —CH₂—O—CH₂—CH₂—CH₂, —CH₂—O—CH₂—CH₂—CH₂—CH₂—, —CH₂—O—CH₂—CH₂—O—CH₂—, —CH₂—NH—CH₂—CH₂, —CH₂—NH—CH₂—CH₂—CH₂, —CH₂—NH—CH₂—CH₂—CH₂—CH₂—, —CH₂—NH—CH₂—CH₂—NH—CH₂— or —CH₂—NH—CH₂—CH₂—O—CH₂—.

C₆-C₁₂arylene is, for example, o-, m- or p-phenylene, 1,4-naphthylene or 4,4′-diphenylene.

Preferably R₁ and R₂ are hydrogen or C₁-C₄alkyl, more preferably hydrogen or methyl.

Preferably R₃, R₄ and R₅ are hydrogen or C₁-C₄alkyl.

The radical A• derived from the group A can be a stable open chain nitroxyl radical or a cyclic nitroxyl radical.

Preferred is a stable cyclic nitroxyl radical.

Preferably the structural element

are part of a 5 to 7-membered heterocyclic ring, which optionally has an additional nitrogen or oxygen atom in the ring system. Substituted piperidine, morpholine and piperazine derivatives are particularly useful.

Preferably the structural element

is a structural element of formula (X)

wherein

G₁, G₂, G₃, G₄ are independently C₁-C₆alkyl or G₁ and G₂ or G₃ and G₄, or G₁ and G₂ and G₃ and G₄ together form a C₅-C₁₂cycloalkyl group;

G₅, G₆ independently are H, C₁-C₁₈alkyl, phenyl, naphthyl or a group COOC₁-C₁₈alkyl;

In particular the structural element of formula (X) is of formula A, B or O described below and thus a preferred compound of the formula (I) or (II); or (Ia), (IIa) or (IIb) is a compound wherein

R₁ and R₂ independently of one another are hydrogen or C₁-C₁₈-alkyl,

R₃, R₄ and R₅ independently of one another are hydrogen or C₁-C₁₈alkyl;

R₆ is hydrogen or C₁-C₁₈alkyl;

X is O, NH or NR₇, wherein R₇ is C₁-C₁₈alkyl,

Y is a direct bond or C₁-C₃₀alkylene

A is a residue of formula A, B or O,

wherein

R₈ is hydrogen, C₁-C₁₈alkyl which is uninterrupted or interrupted by one or more oxygen atoms, cyanoethyl, benzoyl, glycidyl, a monovalent radical of an aliphatic carboxylic acid having 2 to 18 carbon atoms, of a cycloaliphatic carboxylic acid having 7 to 15 carbon atoms, or an α,β-unsaturated carboxylic acid having 3 to 5 carbon atoms or of an aromatic carboxylic acid having 7 to 15 carbon atoms;

R₉ is C₁-C₁₈alkyl, C₅-C₇cycloalkyl, C₂-C₈alkenyl unsubstituted or substituted by a cyano, carbonyl or carbamide group, or is glycidyl, a group of the formula —CH₂CH(OH)-Z or of the formula —CO-Z or —CONH-Z wherein Z is hydrogen, methyl or phenyl;

R₁₀ is C₁-C₁₂alkyl, C₅-C₇cycloalkyl, C₇-C₈aralkyl, C₂-C₁₈alkanoyl, C₃-C₅alkenoyl or benzoyl;

G₁ and G₃ are methyl and G₂ and G₄ are ethyl or propyl or G₁ and G₂ are methyl and G₃ and

G₄ are ethyl or propyl;

G₅ is hydrogen or C₁-C₄alkyl.

Especially preferred is a compound of the formula (I) or (II) or of the formula (Ia), (IIa) or (IIb) wherein

R₁ and R₂ independently of one another are hydrogen or C₁-C₁₈-alkyl,

R₃, R₄ and R₅ is hydrogen,

R₆ is hydrogen,

X is O,

Y is C₁-C₃₀alkylene

A is a residue of formula O,

wherein

G₁ and G₃ are methyl and G₂ and G₄ are ethyl or propyl or G₁ and G₂ are methyl and G₃ and

G₄ are ethyl or propyl;

G₅ is hydrogen or C₁-C₄alkyl.

The above compounds and their preparation are described in GB 2 335 190 and GB 2 361 235 and in U.S. Pat. No. 6,353,107.

Another preferred structural element of formula (X) are those of formula (Xa), (Xb), (Xc), (Xd), (Xe) or (Xf)

wherein R₂₀₁, R₂₀₂, R₂₀₃ and R₂₀₄ independently of each other are C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₃-C₁₈alkinyl, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₃-C₁₈alkinyl which are substituted by OH, halogen or a group —O—C(O)—R₂₀₅, C₂-C₁₈alkyl which is interrupted by at least one O atom and/or NR₂₀₅ group, C₃-C₁₂cycloalkyl or C₆-C₁₀aryl or R₂₀₁ and R₂₀₂ and/or R₂₀₃ and R₂₀₄ together with the linking carbon atom form a C₃-C₁₂cycloalkyl radical;

R₂₀₅, R₂₀₆ and R₂₀₇ independently are hydrogen, C₁-C₁₈alkyl or C₆-C₁₀aryl;

R₂₀₈ is hydrogen, OH, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₃-C₁₈alkinyl, C₁-C₁₈alkyl, C₃-C₁₈alkenyl, C₃-C₁₈alkinyl which are substituted by one or more OH, halogen or a group —O—C(O)—R₂₀₅, C₂-C₁₈alkyl which is interrupted by at least one O atom and/or NR₂₀₅ group, C₃-C₁₂cycloalkyl or C₆-C₁₀aryl, C₇-C₉phenylalkyl, C₅-C₁₀heteroaryl, —C(O)—C₁-C₁₈alkyl, —O—C₁-C₁₈alkyl or —COOC₁-C₁₈alkyl;

R₂₀₉, R₂₁₀, R₂₁₁ and R₂₁₂ are independently hydrogen, phenyl or C₁-C₁₈alkyl.

More preferably in formula (Xa), (Xb), (Xc), (Xd), (Xe) and (Xf) at least two of R₂₀₁, R₂₀₂, R₂₀₃ and R₂₀₄ are ethyl, propyl or butyl and the remaining are methyl; or

R₂₀₁ and R₂₀₂ or R₂₀₃ and R₂₀₄ together with the linking carbon atom form a C₅-C₆cycloalkyl radical and one of the remaining substituents is ethyl, propyl or butyl.

The above compounds and their preparation are described in GB 2342649.

Further suitable compounds are the 4-imino compounds of formula (XI)

wherein

G₁₁, G₁₂, G₁₃ and G₁₄ are independently C₁-C₄alkyl or G₁₁ and G₁₂ together and G₁₃ and G₁₄ together, or G₁₁ and G₁₂ together or G₁₃ and G₁₄ together are pentamethylene;

G₁₅ and G₁₆ are each independently of the other hydrogen or C₁-C₄alkyl;

k is 1, 2, 3, or 4

Y is O, NR₃₀₂ or when n is 1 and R₃₀₁ represents alkyl or aryl Y is additionally a direct bond;

R₃₀₂ is H, C₁-C₁₈alkyl or phenyl;

if k is 1

R₃₀₁ is H, straight or branched C₁-C₁₈alkyl, C₃-C₁₈alkenyl or C₃-C₁₈alkinyl, which may be unsubstituted or substituted, by one or more OH, C₁-C₈alkoxy, carboxy, C₁-C₈alkoxycarbonyl;

C₅-C₁₂cycloalkyl or C₅-C₁₂cycloalkenyl;

phenyl, C₇-C₉phenylalkyl or naphthyl which may be unsubstituted or substituted by one or more C₁-C₈alkyl, halogen, OH, C₁-C₈alkoxy, carboxy, C₁-C₈alkoxycarbonyl;

—C(O)—C₁-C₃₆alkyl, or an acyl moiety of a α,β-unsaturated carboxylic acid having 3 to 5 carbon atoms or of an aromatic carboxylic acid having 7 to 15 carbon atoms;

—SO₃ ⁻Q⁺, —PO(O⁻Q⁺)₂, —P(O)(OR2)₂, —SO₂—R₂, —CO—NH—R₂, —CONH₂, COOR₂, or Si(Me)₃, wherein Q⁺ is H⁺, ammonium or an alkali metal cation;

if k is 2

R₃₀₁ is C₁-C₁₈alkylene, C₃-C₁₈alkenylene or C₃-C₁₈alkynylene, which may be unsubstituted or substituted, by one or more OH, C₁-C₈alkoxy, carboxy, C₁-C₈alkoxycarbonyl;

or xylylene; or

R₃₀₁ is a bisacyl radical of an aliphatic dicarboxylic acid having 2 to 36 carbon atoms, or a cycloaliphatic or aromatic dicarboxylic acid having 8-14 carbon atoms;

if k is 3,

R₃₀₁ is a trivalent radical of an aliphatic, cycloaliphatic or aromatic tricarboxylic acid; and

if k is 4, R₃₀₁ is a tetravalent radical of an aliphatic, cycloaliphatic or aromatic tetracarboxylic acid.

Preferably G₁₆ is hydrogen and G₁₅ is hydrogen or C₁-C₄alkyl, in particular methyl, and

G₁₁ and G₁₃ are methyl and G₁₂ and G₁₄ are ethyl or propyl or G₁₁ and G₁₂ are methyl and G₁₃ and G₁₄ are ethyl or propyl.

The 4 imino compounds of formula (XI) can be prepared for example according to E. G. Rozantsev, A. V. Chudinov, V. D. Sholle.: Izv. Akad. Nauk. SSSR, Ser. Khim. (9), 2114 (1980), starting from the corresponding 4-oxonitroxide in a condensation reaction with hydroxylamine and subsequent reaction of the OH group. The compounds are described in WO 02/100831 (Ciba).

Concerning the nitroxyl radicals the alkyl radicals in the various substituents may be linear or branched. Examples of alkyl containing 1 to 18 carbon atoms are methyl, ethyl, propyl, isopropyl, butyl, 2-butyl, isobutyl, t-butyl, pentyl, 2-pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, t-octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, hexadecyl and octadecyl.

Alkenyl with 3 to 18 carbon atoms is a linear or branched radical as for example propenyl, 2-butenyl, 3-butenyl, isobutenyl, n-2,4-pentadienyl, 3-methyl-2-butenyl, n-2-octenyl, n-2-dodecenyl, iso-dodecenyl, oleyl, n-2-octadecenyl or n-4-octadecenyl.

Preferred is alkenyl with 3 bis 12, particularly preferred with 3 to 6 carbon atoms.

Alkinyl with 3 to 18 is a linear or branched radical as for example propinyl (—CH₂—C≡CH), 2-butinyl, 3-butinyl, n-2-octinyl, or n-2-octadecinyl. Preferred is alkinyl with 3 to 12, particularly preferred with 3 to 6 carbon atoms.

Examples for hydroxy substituted alkyl are hydroxy propyl, hydroxy butyl or hydroxy hexyl.

Examples for halogen substituted alkyl are dichloropropyl, monobromobutyl or trichlorohexyl.

C₂-C₁₈alkyl interrupted by at least one O atom is for example —CH₂—CH₂—O—CH₂—CH₃, —CH₂—CH₂—O—CH₃— or —CH₂—CH₂—O—CH₂—CH₂—CH₂—O—CH₂—CH₃—. It is preferably derived from polyethlene glycol. A general description is —((CH₂)_(a)—O)_(b)—H/CH₃, wherein a is a number from 1 to 6 and b is a number from 2 to 10.

C₂-C₁₈alkyl interrupted by at least one NR₅ group may be generally described as —((CH₂)_(a)— NR₅)_(b)—H/CH₃, wherein a, b and R₅ are as defined above.

C₃-C₁₂cycloalkyl is typically, cyclopropyl, cyclopentyl, methylcyclopentyl, dimethylcyclopentyl, cyclohexyl, methylcyclohexyl or trimethylcyclohexyl.

C₆-C₁₀ aryl is for example phenyl or naphthyl, but also comprised are C₁-C₄alkyl substituted phenyl, C₁-C₄alkoxy substituted phenyl, hydroxy, halogen or nitro substituted phenyl. Examples for alkyl substituted phenyl are ethylbenzene, toluene, xylene and its isomers, mesitylene or isopropylbenzene. Halogen substituted phenyl is for example dichlorobenzene or bromotoluene.

Alkoxy substituents are typically methoxy, ethoxy, propoxy or butoxy and their corresponding isomers.

C₇-C₉phenylalkyl is benzyl, phenylethyl or phenylpropyl.

C₅-C₁₀heteroaryl is for example pyrrol, pyrazol, imidazol, 2, 4, dimethylpyrrol, 1-methylpyrrol, thiophene, furane, furfural, indol, cumarone, oxazol, thiazol, isoxazol, isothiazol, triazol, pyridine, α-picoline, pyridazine, pyrazine or pyrimidine.

If R is a monovalent radical of a carboxylic acid, it is, for example, an acetyl, propionyl, butyryl, valeroyl, caproyl, stearoyl, lauroyl, acryloyl, methacryloyl, benzoyl, cinnamoyl or β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl radical.

C₁-C₁₈alkanoyl is for example, formyl, propionyl, butyryl, octanoyl, dodecanoyl but preferably acetyl and C₃-C₅alkenoyl is in particular acryloyl.

Particularly suitable nitroxyl radicals are those of formulae

In a very specific embodiment the nitroxyl radical is

Preparation 1. Preparation of the Compounds of Formula I

The nitroxyl radicals which are the precursors of the group A of formula (I)-(VI) are known and may be prepared according to WO 99/03984, (Ciba) EP-A-0 891 986 (Ciba) or WO 98/13392 (Akzo).

The preparation of compounds of formula (I) or (II) can be performed by reacting nitroxyl radicals A* with the following carbon centered radicals:

One, but not the only one, possibility is the reaction of the nitroxides A* with the following halogen derivatives transition metal such as for example Cu or Cu(I) salt, for example CuCl or CuBr, and optionally suitable ligand, for example 2, 2′ bipyridyl or pentamethyldiethylenetriamine. See K. Matyjaszewski, B. E. Woodworth, X. Zhang, Scott G. Gaynor, Z. Metzner.: Macromolecules 31, 5955-5957 (1998).

The above halogen derivatives can be easily prepared by well-known organic reactions, for example acylation of the corresponding alcohols or amines with suitable haloacid derivatives.

EXAMPLES Example 1 Preparation of α,o-Poly-(n-butyl acrylate)-co-(polysiloxane) [A-B-A structure]

In a 100 ml three neck flask, equipped with thermometer, cooler and magnetic stirrer, 6.00 g (18.4 mmol) of regulator A*) [structure see below], 13.0 g (18.2 mmol) of an α,o-dihydrogen dimethylpolysiloxane [M_(n) ˜1428 g/mol; SiH=1.4 mmol/g] and 20 g of xylene are mixed and degassed twice. The clear solution obtained is heated under nitrogen to 90° C. At this temperature 20 mg of hexachloroplatinic acid solution [0.01 mmol Pt/g i-propanol] is injected. A slightly exothermic reaction is observed. The hydrosilylation is carried out to a residual SiH-value <0.02 mmol/g. Xylene is removed by distillation under reduced pressure. 50 g (390 mmol) of n-butyl acrylate is added. The mixture is degassed twice, heated to 130° C. and polymerization is carried out to a solid content of ˜50%. The remaining volatiles (˜44.5 g) are removed by distillation under vacuum.

44.5 g of a clear yellowish viscous fluid is obtained.

GPC: M_(n)=6018 g/mol; M_(w)=7798 g/mol PD=1.29

Regulator A*):

Example 2 Preparation of Poly-(n-butyl acrylate)-co-(polysiloxane) [Comb structure]

In a 100 ml three neck flask, equipped with thermometer, cooler and magnetic stirrer, 2.60 g (8.0 mmol) of regulator A*) [structure see above, 5.0 g (16.0 mmol) of a comb-like H-dimethylpolysiloxane [M_(n) ˜1500 g/mol; SiH=3.2 mmol/g] and 20 g of xylene are mixed and degassed twice. The clear solution obtained is heated under nitrogen to 80° C. At this temperature 20 mg of hexachloroplatinic acid solution [0.01 mmol Pt/g i-propanol] is injected. A slightly exothermic reaction is observed. The residual SiH content is reacted away by addition of octene. The hydrosilylation is carried out to a residual SiH-value <0.02 mmol/g. Xylene/octene is removed by distillation under reduced pressure.

80 g (624 mmol) of n-butyl acrylate is added. The mixture is degassed twice, heated to 130° C. and polymerization is carried out to a solid content of ˜50%. The remaining volatiles (˜45 g) are removed by distillation under vacuum.

44.5 g of a clear yellowish viscous fluid is obtained.

GPC: M_(n)=7775 g/mol; M_(w)=11042 g/molPD=1.42

Examples 3-10 were carried out in the same way described in Example 2.

H-Siloxane GPC Product [SiH content (mmol/g)/ data Example Regulator A M_(n) (g/mol)/structure] Octene [M_(n)/M_(w)/PD]* 3 3.50 g 5.00 g [3.2/1500/C*] 2.00 g 10181/20891/2.05  4 3.00 g 3.00 g [3.15/635/L*] 0.00 g 9351/12910/1.38 5 3.00 g 6.50 g [1.4/1428/L] 0.00 g 7775/11042/1.42 6 3.00 g 4.95 g [1.84/1087/L] 0.00 g 7623/10198/1.34 7 2.52 g 5.00 g [6.2/940/C] 5.00 g 12791/26494/2.07  8 2.27 g 5.00 g [6.9/2050/C] 6.00 g 17359/38804/2.24  9 2.50 g 3.60 g [3.2/1650/C] 1.00 g 8560/19906/2.33 10 3.00 g 3.60 g [2.2/2700/C] 1.00 g 7361/22983/3.12 C*comb-like siloxanes (i.e. -[(Me)₂SiO]_(n)[MeSiHO]_(m)—) L*α,o-dihydrogen siloxanes (i.e. HMe₂SiO[(Me)₂SiO]_(n)[Me₂SiH) [M_(n)/M_(w)/PD]*mol weight distribution/polydispersity Application Results Anti Crater Performance

A Anti Crater Performance in 2 Pack PU

1) Formulation 2 Pack Polyurethane

TABLE 1 2 pack PU system/two component PU coating (g) 1) Synthalat A 150 (polyurethane available from Synthapol) 88.6 2) Blue colorant (g) 1.5 3) Butyl Acetate (g) 11.3 4) EFKA-2018 (g) (defoamer) 5.0 Total 100.0

-   -   The products 1 till 3 are shaken for 5 min in a skandex shaker.     -   After shaken, position number 4 is added and mixed in         homogeneously.

2) Formulations for anti crater performance tests of the siloxane modified acrylic leveling agent:

TABLE 2 1 2 3 4 1) 2 pack PU (g) 74.00 73.63 73.26 72.52 2) Example 1-20 (g) 0.00 0.50 1.00 2.00 3) Desmodur N 75 (g) 26.00 25.87 25.74 25.48 Polyisocyanate resin Total 100.00 100.00 100.00 100.00

-   -   Positions 1 to 3 are agitated homogeneously by spatula.     -   After mixing, let the samples rest for 1 hour before preparing         the draw down.

3) Application

Draw downs are prepared using a 75 μm wire bar.

4) Results

TABLE 3 Examples 1 2 3 4 0% 0.5% 1.0% 2.0% Comparative 8 6 5 3 1 8 1 1 1 2 8 3 2 1 3 8 2 1 1 4 8 1 1 1 5 8 1 1 1 6 8 1 1 1 7 8 2 1 1 8 8 2 1 1 9 8 3 2 1 10 8 2 1 1 1 = no craters; 8 = a lot of craters.

B Slip Performance in Stoving Enamel

1) Formulation Stoving Enamel:

TABLE 4 Stoving enamel (g) 1) Vialkyd AC 451 71.4 2) Maprenal MF 650 19.5 3) Butyl Acetate 10.1 Total 100.0

Positions 1 to 3 are agitated to a homogeneous mixture.

2) Formulations for Slip Performance Tests of the Siloxane Modified Acrylic Leveling Agent:

TABLE 5 0.5% 1.0% 1) Stoving enamel (g) 99.50 99.00 2) Example 1-10 (g) 0.50 1.00 Total 100.00 100.00

3) Preparation of the Draw Downs:

-   -   Draw downs of 75 μm are prepared on plastic films.     -   The draw downs have to rest for 10 minutes before curing.     -   Bake out time 30 min@135° C.

4) Results Coefficient of Friction:

TABLE 6 Dynamic COF comparative Ex. 1 Ex. 2 Ex. 3 Ex. 4 2) 0.5% 0.33 0.19 0.24 0.26 0.21 3) 1.0% 0.31 0.19 0.23 0.25 0.20 Dynamic COF Ex. 5 Ex. 6 Ex. 7 Ex. 8 Ex. 9 Ex. 10 2) 0.5% 0.24 0.26 0.23 0.24 0.29 0.25 3) 1.0% 0.22 0.24 0.22 0.26 0.28 0.24 

1. A compound of formula (I) or (II)

wherein A is a group of formula A, B or O capable of forming a stable free nitroxyl radical A• which is bound via its oxygen atom to the carbon atom

 wherein R₈ is hydrogen, C₁-C₁₈alkyl which is uninterrupted or interrupted by one or more oxygen atoms, cyanoethyl, benzoyl, glycidyl, a monovalent radical of an aliphatic carboxylic acid having 2 to 18 carbon atoms, of a cycloaliphatic carboxylic acid having 7 to 15 carbon atoms, or an α,β-unsaturated carboxylic acid having 3 to 5 carbon atoms or of an aromatic carboxylic acid having 7 to 15 carbon atoms; R₉ is C₁-C₁₈alkyl, C₅-C₇cycloalkyl, C₂-C₈alkenyl unsubstituted or substituted by a cyano, carbonyl or carbamide group, or is glycidyl, a group of the formula —CH₂CH(OH)—Z or of the formula —CO—Z or —CONH—Z wherein Z is hydrogen, methyl or phenyl; R₁₀ is C₁-C₁₂alkyl, C₅-C₇cycloalkyl, C₇-C₈aralkyl, C₂-C₁₈alkanoyl, C₃-C₅alkenoyl or benzoyl; G₁ and G₃ are methyl and G₂ and G₄ are ethyl or propyl or G₁ and G₂ are methyl and G₃ and G₄ are ethyl or propyl; G₅ is hydrogen or C₁-C₄alkyl, R₁ and R₂ independently of one another are hydrogen, C₁-C₁₈-alkyl, C₃-C₈cycloalkyl or phenyl which are unsubstituted or substituted by NO₂, halogen, amino, hydroxy, cyano, carboxy, C₁-C₄alkoxy, C₁-C₄alkylthio, C₁-C₄alkylamino or di(C₁-C₄alkyl)amino; R₃, R₄ and R₅ independently of one another are hydrogen or C₁-C₁₈alkyl or phenyl; or R₃ and R₅ together with the linking group C═C form a 5 to 12 membered ring; R₆ is hydrogen or C₁-C₁₈alkyl or phenyl; X is O, NH or NR₇, wherein R₇ is C₁-C₁₈alkyl, C₃-C₈cycloalkyl or phenyl; Y is a direct bond, C₁-C₃₀alkylene or C₆-C₁₂arylene.
 2. The compound of the formula (I) or (II) according to claim 1 wherein R₁ and R₂ independently of one another are hydrogen or C₁-C₁₈-alkyl, R₃, R₄ and R₅ independently of one another are hydrogen or C_(l)-C₁₈alkyl; R₆ is hydrogen or C₁-C₁₈alkyl; X is O, NH or NR₇, wherein R₇ is C₁-C₁₈alkyl, Y is a direct bond or C₁-C₃₀alkylene.
 3. The compound of the formula (I) or (II) according to claim 1 wherein R₁ and R₂ independently of one another are hydrogen or C₁-C₁₈-alkyl, R₃, R₄ and R₅ is hydrogen, R₆ is hydrogen, X is O, Y is C₁-C₃₀alkylene, A is a residue of formula O

 wherein G₁ and G₃ are methyl and G₂ and G₄ are ethyl or propyl or G₁ and G₂ are methyl and G₃ and G₄ are ethyl or propyl; G₅ is hydrogen or C₁-C₄alkyl.
 4. A polysiloxane modified initiator/regulator of the formula

wherein A is a group of formula A, B or O capable of forming a stable free nitroxyl radical A• which is bound via its oxygen atom to the carbon atom

 wherein R₈ is hydrogen, C₁-C₁₈alkyl which is uninterrupted or interrupted by one or more oxygen atoms, cyanoethyl, benzoyl, glycidyl, a monovalent radical of an aliphatic carboxylic acid having 2 to 18 carbon atoms, of a cycloaliphatic carboxylic acid having 7 to 15 carbon atoms, or an α,β-unsaturated carboxylic acid having 3 to 5 carbon atoms or of an aromatic carboxylic acid having 7 to 15 carbon atoms; R₉ is C₁-C₁₈alkyl, C₅-C₇cycloalkyl, C₂-C₈alkenyl unsubstituted or substituted by a cyano, carbonyl or carbamide group, or is glycidyl, a group of the formula —CH₂CH(OH)—Z or of the formula —CO—Z or —CONH—Z wherein Z is hydrogen, methyl or phenyl; R₁₀ is C₁-C₁₂alkyl, C₅-C₇cycloalkyl, C₇-C₈aralkyl, C₂-C₁₈alkanoyl, C₃-C₅alkenoyl or benzoyl; G₁ and G₃ are methyl and G₂ and G₄ are ethyl or propyl or G₁ and G₂ are methyl and G₃ and G₄ are ethyl or propyl; G₅ is hydrogen or C₁-C₄alkyl, R₁ and R₂ independently of one another are hydrogen, C₁-C₁₈-alkyl, C₃-C₈cycloalkyl or phenyl which are unsubstituted or substituted by NO₂, halogen, amino, hydroxy, cyano, carboxy, C₁-C₄alkoxy, C₁-C₄alkylthio, C₁-C₄alkylamino or di(C₁-C₄alkyl)amino; R₃, R₄ and R₅ independently of one another are hydrogen or C₁-C₁₈alkyl or phenyl; or R₃ and R₅ together with the linking group C═C form a 5 to 12 membered ring; R₆ is hydrogen or C₁-C₁₈alkyl or phenyl; X is O, NH or NR₇, wherein R₇ is C₁-C₁₈alkyl, C₃-C₈cycloalkyl or phenyl; Y is a direct bond, C₁-C₃₀alkylene or C₆-C₁₂arylene, a is 1 or 2, or a whole number between 1 and 100, W is a linear or branched monofunctional, difunctional or multifunctional polysiloxane residue.
 5. The polysiloxane modified initiator/regulator according to claim 4, wherein W is derived from


6. The compound of the formula (Ia), (IIa) or (IIb) according to claim 4 wherein R₁ and R₂ independently of one another are hydrogen or C₁-C₁₈-alkyl, R₃, R₄ and R₅ independently of one another are hydrogen or C₁-C₁₈alkyl; R₆ is hydrogen or C₁-C₁₈alkyl; X is O, NH or NR₇, wherein R₇ is C₁-C₁₈alkyl, Y is a direct bond or C₁-C₃₀alkylene.
 7. The compound of the formula (Ia), (IIa) or (IIb) according to claim 4 wherein R₁ and R₂ independently of one another are hydrogen or C₁-C₁₈-alkyl, R₃, R₄ and R₅is hydrogen, R₆ is hydrogen, X is O, Y is C₁-C₃₀alkylene, A is a residue of formula O

 wherein G₁ and G₃ are methyl and G₂ and G₄ are ethyl or propyl or G₁ and G₂ are methyl and G₃ and G₄ are ethyl or propyl; G₅ is hydrogen or C₁-C₄alkyl.
 8. A siloxane modified polymer or copolymer which is obtained by a) reacting a Si-H functionalized polysiloxane in the presence of a functional alkoxyamine initiator/regulator compound of the formula (I) or (II)

 under hydrosilylation conditions to obtain alkoxyamine functional polysiloxanes (Ia), (IIa) or (IIb)

b) reacting the resulting alkoxyamine functional polysiloxane polysiloxanes (Ia), (IIa) or (IIb) with at least one vinylic monomer at a temperature between 60 and 160° C. wherein A is a group of formula A, B or O capable of forming a stable free nitroxyl radical A• which is bound via its oxygen atom to the carbon atom

 wherein R₈ is hydrogen, C₁-C₁₈alkyl which is uninterrupted or interrupted by one or more oxygen atoms, cyanoethyl, benzoyl, glycidyl, a monovalent radical of an aliphatic carboxylic acid having 2 to 18 carbon atoms, of a cycloaliphatic carboxylic acid having 7 to 15 carbon atoms, or an α,β-unsaturated carboxylic acid having 3 to 5 carbon atoms or of an aromatic carboxylic acid having 7 to 15 carbon atoms; R₉ is C₁-C₁₈alkyl, C₅-C₇cycloalkyl, C₂-C₈alkenyl unsubstituted or substituted by a cyano, carbonyl or carbamide group, or is glycidyl, a group of the formula —CH₂CH(OH)—Z or of the formula —CO—Z or —CONH—Z wherein Z is hydrogen, methyl or phenyl; R₁₀ is C₁-C₁₂alkyl, C₅-C₇cycloalkyl, C₇-C₈aralkyl, C_(2 -C) ₁₈alkanoyl C₃-C₅alkenoyl or benzoyl; G₁ and G₃ are methyl and G₂and G₄ are ethyl or propyl or G₁ and G₂ are methyl and G₃ and G₄ are ethyl or propyl; G₅hydrogen or C₁-C₄alkyl, R₁ and R₂ independently of one another are hydrogen, C₁-C₁₈-alkyl, C₃-C₈cycloalkyl or phenyl which are unsubstituted or substituted by NO₂, halogen, amino, hydroxy, cyano, carboxy, C₁-C₄alkoxy, C₁-C₄alkylthio, C₁-C₄alkylamino or di(C₁-C₄alkyl)amino; R₃, R₄ and R₅ independently of one another are hydrogen or C₁-C₁₈alkyl or phenyl; or R₃ and R₅ together with the linking group C═C form a 5 to 12 membered ring; R₆ is hydrogen or C₁-C₁₈alkyl or phenyl; X is O, NH or NR₇, wherein R₇ is C₁-C₁₈alkyl, C₃-C₈cycloalkyl or phenyl; Y is a direct bond, C₁-C₃₀alkylene or C₆-C₁₂arylene, with the proviso that the compound of formula I is not

a is 1 or 2, or a whole number between 1 and 100, W is a linear or branched monofunctional, difunctional or multifunctional polysiloxane residue.
 9. A method for improving anti-crater performance or slip performance by mixing into a formulation a siloxane modified polymer or copolymer of claim 8 as slip and leveling agent or as dispersant.
 10. A siloxane modified polymer or copolymer slip and leveling agent of claim 8 wherein the vinylic monomer is selected from methylacrylate, ethylacrylate, ethylhexylacrylate, propylacrylate, cyclohexylacrylate, hydroxyethylacrylate, n-butylacrylate, styrene, vinylpyridine. 